1. Field of the Invention
The present invention relates to wireless communication and, more particularly, to a method of transmitting control information through uplink and a wireless device using the same.
2. Background Art Related Art
The next-generation multimedia wireless communication systems now being actively researched are required to process and send various pieces of information, such as video and wireless data out of the early voice-centered service. The 4th generation wireless communication systems being developed which are subsequent to the current 3rd generation wireless communication systems are aiming at supporting high-speed data service of downlink 1 Gigabit per second (Gbps) and of uplink 500 Megabits per second (Mbps). An object of a wireless communication system is to enable a number of users to perform reliable communication irrespective of their locations and mobility. However, a wireless channel has abnormal characteristics, such as a path loss, noise, a fading phenomenon attributable to multi-path, Inter-Symbol Interference (ISI), and the Doppler effect resulting from the mobility of a terminal. A variety of techniques are being developed in order to overcome the abnormal characteristics of wireless channels and to increase the reliability of wireless communication.
Long Term Evolution (LTE) based on 3rd Generation Partnership Project (3GPP) Technical Specification (TS) Release 8 is a leading next-generation mobile communication standard.
As disclosed in 3GPP TS 36.211 V8.7.0 (2009-05) “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 8)”, in LTE, physical channels may be divided into a Physical Downlink Shared Channel (PDSCH) and a Physical Downlink Control Channel (PDCCH), that is, downlink channels, and a Physical Uplink Shared Channel (PUSCH) and a Physical Uplink Control Channel (PUSCH), that is, uplink channels.
A PUCCH is an uplink control channel that is used to send uplink control information, such as a Hybrid Automatic Repeat reQuest (HARM) acknowledgement/not-acknowledgement (ACK/NACK) signal, a Channel Quality Indicator (CQI), and a Scheduling Request (SR).
Meanwhile, 3GPP LTE-Advanced (A), that is, the evolution of 3GPP LTE, is in progress. Technology introduced into 3GPP LTE-A includes a Carrier Aggregation (CA) and Multiple Input Multiple Output (MIMO) supporting four or more antenna ports.
A CA uses a plurality of component carriers. A component carrier is defined by the center frequency and the bandwidth. A single downlink component carrier or a pair of an uplink component carrier and a downlink component carrier corresponds to a single cell. It may be said that a terminal supplied with service using a plurality of downlink component carriers is supplied with service from a plurality of serving cells.
Furthermore, research is being carried out on structure/schemes for sending HARQ ACK/NACK, Channel State Information (CSI) and/or sounding, that is, control information in 3GPP LTE-A, the definition of a CA environment, and control technology.